The fundamental of LTA is a structure that can withstand a large pressure differential.
My idea is for a material that, on heating, sets. It is composed of flexible sheets with fibres embeded between the layers. This composite material is placed in an extreme vacuum mold where the sheets are sucked
apart. The stretched fibre forms supporting voronoi struts between sheets. The whole vacuum formed bubble is heat treated.
The space inside the solid cell has no other gases other than supporting fibre struts. Cells after manufacture have to be strapped down least they escape.
Flight captain: " Tower, this is Hyperbird one fifty, whats the thirty thousand foot Alantic patch looking like today?"
Tower: "Hyperbird one fifty, This is Tower. Dense, the cleanup drones have been down for maintenance. Tower out."